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تسجيل مستخدم جديدDynamical density and spin response of Fermi arcs and their consequences for Weyl semimetals
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Weyl semimetals exhibit exotic Fermi-arc surface states, which strongly affect their electromagnetic properties. We derive analytical expressions for all components of the composite density-spin response tensor for the surfaces states of a Weyl-semimetal model obtained by closing the band gap in a topological insulating state and introducing a time-reversal-symmetry-breaking term. Based on the results, we discuss the electromagnetic susceptibilities, the current response, and other physical effects arising from the density-spin response. We find a magnetoelectric effect caused solely by the Fermi arcs. We also discuss the effect of electron-electron interactions within the random phase approximation and investigate the dispersion of surface plasmons formed by Fermi-arc states. Our work is useful for understanding the electromagnetic and optical properties of the Fermi arcs.
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The Weyl semimetal phase is a recently discovered topological quantum state of matter characterized by the presence of topologically protected degeneracies near the Fermi level. These degeneracies are the source of exotic phenomena, including the rea
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It is well known that on the surface of Weyl semimetals, Fermi arcs appear as the topologically protected surface states. In this work, we give a semiclassical explanation for the morphology of the surface Fermi arcs. Viewing the surface states as a
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